This invention relates generally to the field of optical alignment systems and more particularly to a novel optical device for detecting misalignment in a binocular display by superimposition of the two binocular display images.
The present invention provides a simple and easy-to-use device for determining the disparity between the images transmitted along the optical axes of a binocular display system. The invention finds particular utility for the alignment, adjustment or calibration of binocular helmet mounted displays and other optical devices employing wide field of view binocular displays.
The invention comprises a pair of objective lenses for receiving the images transmitted along the two optical axes of the binocular display and focusing the images on an imaging plane for viewing. The images transmitted by the objective lenses are folded onto a single optical axis, using folding mirrors, right angle prisms, or the like, inserted along each optical axis of the binocular system, and displayed on a reticle mounted in the imaging plane as a single superimposed image. Means may be included to provide equal optical path lengths along each binocular optical axis from the lenses to the reticle. For a properly aligned binocular display system, the two images transmitted along the two binocular optical axes and superimposed using the optics of the present invention will appear as a single, well-defined image on the imaging plane. Disparity in alignment of the binocular display between the two optical axes is detected by the device of the present invention as a diffuse or double image.
It is therefore an object of the present invention to provide an improved optical alignment device.
It is a further object of the present invention to provide a device for detecting misalignment of a binocular optical display system.
It is yet another object of the present invention to provide a device for checking the alignment of helmet mounted binocular displays.
These and other objects of the present invention will become apparent as the detailed description of certain representative embodiments thereof proceeds.